Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the annotations (readOnlyHint, openWorldHint, idempotentHint, destructiveHint), the description adds substantial behavioral context: returns exactly 25 receipts, newest-first ordering, pagination via 'nextCursor as beforeId', immutability of receipts, and that they contain only locators/hashes, not original text. This significantly helps an agent anticipate the tool's output and behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, all purposeful and front-loaded with the primary action. No fluff or repetition. The pagination instruction and content caveat are efficient and necessary.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (5 parameters, nested objects, no output schema), the description provides useful workflow and return-value context but omits explanation of the meaning of expectedReadRevision and contextRevision. It is more complete than average, but the parameter gaps prevent a perfect score.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 20%, so the description should compensate, but it does not explain the key parameters (projectId, contextRevision, sourceKey, expectedReadRevision) beyond a brief mention of beforeId/nextCursor in the pagination context. The 'current source session' concept is not tied to any parameter. This leaves the agent guessing how to construct a correct request.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('Read'), a precise resource ('25 immutable page receipts'), and the scope ('current source session'). It clearly distinguishes from sibling tools like read_original_page (which would fetch original text) by explicitly noting receipts contain 'locators/hashes, never original source text.'

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear context for when to use the tool: to recover exact page revisions after interruption, with an explicit workflow hint ('replay them through read_original_page'). It does not explicitly name alternatives like read_document_provenance or list_document_versions, nor provide when-not-to-use instructions, so it falls short of a full 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.